Cylindrical kiln and drier



e. McCRAE.

CYLINDRICAL KILN AND DRIER.

APPLICATION FILED OCT-.6. 1920.

INVE NT UH...

Patented De an lilo-Al n u "t e a" n w v.15 P will all. at

CYLINZDTRICAL KILN .ttJSlD DRIER.

Application filed October 6, 1920 To all to/lam it may concern li e it known that l, llnonon ilioCrn in, ot the city oi Brantt'ord, in the county o't Brant, Province of Ontario, Canada, have nvented certaln new and useful improvements in Cylindrical Kilns and Driers, oi? which the following is a specification.

This invention relates to cylindrical kilns, usually rotary, in which solid materials are subjected to the action of heat, and particularly to kilns for operating on materials which, in whole or part, require to be dried or preheated before entering the kiln, and my objectis to devise a kiln which, without any increase in length, is adapted to preheat such material.

fl" attain my object by employing a kiln having longitudinal external ribs, such tor example as the kiln described and shown in my Canadian patent application No. 240053 filed April 14th, 1920, and by securing an outer sectional shell outside the kiln to form an annular preheating space outside the kiln, such sectional shell being provided with flanges secured to the ribs aforesaid.

The kiln is hereinafter more specifically described and illustrated in the accompany ing drawings in which- Figure l is a side elevation, partly broken away, of my cylindrical kiln;

Fig. 2 a cross section on an enlarged scale of. part of the kiln; and

Fig. 3 a side elevation, partly in section, of part out the kiln on the same scale Fig. 2.

In the drawings like numerals of reference indicate corresponding parts in the dilterent figures.

The kiln, as will be seen from F ig. 1 of the drawings, is in general of ordinary type, and is shown as adapted for rotation, 1 be ing the circular tracks commonly employed and 2 the sheaves or pulleys wherebv power may be applied to rotate the kiln. Oi course, any ordinary gearing may be employed for this purpose. As indicated particularly in Figs. 2 and 8 of the drawings, the kiln, instead of being made of lapped and riveted plates, is formed oil a plurality of longitudinal sections 3, each section being provided along each of its straight edges with a radial flange l, these flanges extending outwardly a suflicient distance to provide suitable space for the bolts or rivets by which they are secured together.

To the interior of the shell the refractory specification of Letters Patent.

Patented Dec. d, ttmll.

tlcrial no. aiaiae.

lining 5 will be secured in any ordinary manner.

@utside the kiln, between any two of the circular tracks 1, l secure a cylindrical casing, preferably formed o:t sections 6. This sectional shell may be secured to the kiln in any suitable manner. I prefer, however, to secure the shell to the ribs or :tlanges l, the external shell being provided with flanges l, which may be riveted or bolted to the flanges l. in the preferred construction each section is provided with an inwardly turned flange 7 secured to one of the flanges at and an outwardly extending flange 8, the flanges 8 ct two adjoining sections being in juxtaposition and bolted or riveted together. This external shell is preferably toriiled as a truncated cone to facilitate discharge oi any material introduced into the space be tween the two shells to be dried or preheated. This necessarily means, oi. course, that the flanges 7 taper in the direction of their length. Despite the fact of lining the kiln, a good deal ct heat is conducted to the outer surface 01"" the kiln and is there radiated and lost. With my construction, I am enabled to utilise this otherwise waste heat to preheat or dry any oi the products which are subsequently to be introduced into the interior oi? the kiln, and my invention is particularly adapted for use in cement kilns to preheat part or all of the constituents oi which the cement is manufactured.

To permit of the escape or moisture laden air ll provide vents 9 in the external shell 6. These air vents are preferably formed as pipes having their inner ends bent in the direction oi the flow oft material in order to prevent leakage of the latter.

What I claim as'my invention is l. A cylindrical kiln comprising a metallic shell; annular members longitudinally spaced apart and secured to the shell tor sup porting or rotating the latter; and an external sectional shell secured to and spaced from the kiln shell and intermediate two adj acent members.

2. it cylindrical kiln comprising a metallic shell having external longitudinal ribs formed thereon; annular members longitudinally spaced apart and secured to the shell. for supporting or rotating the latter; and an external sectional shell. secured to said ibs and spaced from the kiln shell and intermediate two adjacent members.

8. A cylindrical kiln comprising a metallic shell; an external shell secured to the kiln shell and spaced therefrom, the external shell being shaped substantially as a trimcated cone. 7 r

4. A cylindrical kiln comprising a metallic shell having external longitudinal ribs formed thereon; an external sectional shell spaced from the kiln shell and secured to said ribs.

5. A cylindrical kiln comprising a metallic shell having external longitudinal ribs formed thereon; an external sectional shell spaced from the kiln shell and having flanges on the sections secured to the ribs.

, 6. A cylindrical kiln comprising a metallic shell having external longitudinal ribs formed thereon; an external sectional shell spaced from the kiln shell and having flanges on the sections secured to the ribs, the external shell being shaped substantially as a truncated cone.

7. A cylindrical kiln comprising a metallic shell; an external shell secured to the kiln shell and spaced therefrom; a bent pipe mounted in the external shell communicating with the space between the shells, the inner end of the pipe being bent to face in the direction of the flow of material in the space.

Signed at city of Brantford, this 19th day of August, 1920.

GEORGE MGCRAE. 

